1. FIELD of the INVENTION
The invention relates to closure devices for sealing containers. More particularly, the invention relates to closure devices for sealing container spouts while providing a means to relieve any excessive pressure which may exist in the container.
2. DESCRIPTION of the PRIOR ART
Containers provided with spouts have an obvious utility to consumers as, among other things, product applicators for directing the container contents in a concentrated stream to a predetermined point. If a container intended for use with a spout is already filled with product prior to purchase by a consumer, the container must be sealed to prevent spillage during shipment and prior to use.
One method of shipping such a filled container having contents intended for use with a container spout is to use a conventional, threaded closure cap sealing the container during shipment and an auxiliary spout packaged with the sealed container. A consumer could alternate the cap and spout as desired. This method obviously requires an extra part to be manufactured for use of the container contents and is, therefore, costly. It would be preferable to ship and sell to consumers a container with a spout already threaded on the container so that no separate closure cap is necessary. Where spout orifice size is not critical, such containers are provided with sealed spout tips which must be cut off prior to use. However, this conventional method is incapable of venting excessive pressures in the container while sealing the container.
If a product is capable of generating excessive internal pressures within a container, the product is shipped and sold with its component parts separated. A consumer must mix the parts prior to use. Certain products such as hair coloring products are generally packaged for consumers in the form of a container of hydrogen peroxide or other peroxide based developer sealed with a conventional threaded tapered spout and a separate package of dyestuff. The consumer can remove the sealed threaded spout and mix the dyestuff and developer in the container to prepare the hair dye. To use the product, the consumer must snip the tip of the sealed spout to create an orifice of desired size and also to vent the pressure created within the container by the dyestuff/developer mixture.
This type of container and spout combination has several deficiencies: the spout tip must be cut off with an auxiliary cutting tool which must be supplied by the consumer; the size of the orifice created by various consumers may not be uniform, thus creating the opportunity for the product to be improperly used; the cutting process may create a sharp edge at the tip and this presents a danger of irritation to the consumer's scalp during use; if a consumer inadvertently replaces the spout cap after mixing the components without snipping the tip, the internal pressure in the container builds to a dangerous level creating the possibility of explosion because there is no pressure venting means. To enhance consumer convenience and safety, a spout closure is needed which may be manually opened, without auxiliary tools, to provide a uniform, smooth orifice and which is capable of venting excessive internal pressure. The spout closure should be capable of being placed on a spout after the spout is opened in order to provide at least a partial closure to limit or prevent spillage.
Several types of container closures are known in the prior art. Examples of those which are suitable for sealing container spouts are, however, limited. U.S. Pat. No. 2,887,240 discloses a tapered spout, the tip of which is sealed during shipment and intended to be cut by the consumer prior to use. A separate cap is provided which may thereafter be used to enclose the orifice of the cut spout. The closure shown in this patent does not overcome the deficiencies cited above.
U.S. Pat. No. 3,253,728 shows a cylindrical, non-tapered, extensible spout provided with a manually removable closure cap. The cap is provided with an annular bead along its bottom rim for engaging an annular groove in the spout tip. There is no means shown for easily removing the closure cap other than forcibly deforming it to disengage the annular rib from the groove. Also, there is no means in this device for venting any excessive pressure built up within the container.
U.S. Pat. No. 2,886,198 discloses a closure cap for a bottle orifice which closure may be adapted to a spout. The closure in this patent is constructed of a resilient material and is provided with a pull lug extending from the cap and connected to the bottom portion of the closure which covers the orifice of the container. A thinned portion of the closure facilitates the tearing away of the pull lug and closure portion connected to it. The pull lug of this closure extends obtrusively from the closure and is therefore likely to be accidentally pulled or torn, thus opening the closure prematurely. Also, there is no means provided with this closure for venting any excessive pressure built up in the container.
U.S. Pat. No. 1,134,068 shows a closure for an outwardly tapered jar. The closure is provided with a pull tab generally aligned with the external surface of the jar. While this pull tab is not obtrusive, the closure itself is made of metal and is intended to be deformed by pulling the pull tab, thus removing the closure. Since the closure is assembled with the use of machinery required to deform an annular rim of the closure, a consumer would be unable to reseal the container effectively. Also, there is no means shown in this patent for relieving any internal pressure built up in the container.
In view of the above, it is an object of this invention to provide a manually removable closure cap for a container spout. It is a further object of this invention to provide a closure for a container spout which closure may be easily removed by a consumer without the necessity for any cutting or other implements.
It is yet another object of this invention to provide a manually removable closure cap for a container spout which closure cap effectively seals the container contents prior to being opened by a consumer and which permits venting of any excessive pressure built up in the container.